There are few weather events that cause apprehension or fear to the people of central West Virginia like that of the Great Derecho of 2012. Historic floods in 1967, 1985, and most recently in 2016 may provide similar feelings of dread, but this was a severe weather event instead of a flood. Today marks the fifth anniversary of one of the strongest storms to ever impact the Mountain State. For some people, power outages would extend two weeks. Gasoline shortages became common, with many running generators as many gas stations remained without power. The lines that formed to purchase gasoline in combination with the serious heat in the days to come would cause fights at stores, not something our area is used to seeing. To this day, many inhabitants of the Mountain State will be able to tell you how they endured the widespread damage-causing event, and what they did in the aftermath to stay alive.
SETUP AND EVENT
A morning surface analysis on June 27th, 2012 showed no real evidence of a significant weather event on the horizon. One thing for sure though that could be seen – a serious heat wave was on the horizon, even for our region. Our weather maker that would become the Great Derecho of 2012 was well west in the Upper Plains. Thanks to an area of high pressure nearly over our area, temperatures were soared for high temperatures that day in the middle section of the country, with high temperatures of 115 in Graham County, Kansas (KHLC) and 111 in Miles City, Montana (KMLS).
By June 28th, the area of high pressure over our area was overpowered by a much more broader area of high pressure over the Gulf of Mexico. The southwesterly winds from that high pressure made its way into our region, and so the record stretch of weather began in West Virginia. Charleston received its first 100 degree day since August 2008, with Huntington reaching 101 degrees and Jackson, Kentucky reaching 100. Over 20 states reached at least 100 degrees on June 28th, which displays the broad area of extreme heat that gripped the eastern half of the United States.
In addition, the frontal boundary that would cause our widespread severe weather the next day was moving in our doorstep, causing severe weather across portions of the Midwest, including Illinois.
By the morning of June 29th, the meteorologists at the Storm Prediction Center began to monitor for the possibility of a developing bow echo across the upper Ohio Valley, as shown in their severe weather outlook and statement issued at 13Z that morning. This issuance was declared due to a complex of thunderstorms that initiated across parts of Iowa and western Illinois in addition to energy created by extreme heat across the region.
The complex that would become known as the Great Derecho of 2012 for the Mid-Atlantic states began as a small complex late June 28th in the Midwest. By the early morning of June 29th, a complex of thunderstorms formed along a cold front in the Midwest states of Illinois, Iowa, and Missouri along. Our broad area of high pressure that fueled triple digit the day prior on June 28th remained in the deep south on the 29th, ushering in a continued southwesterly breeze ahead of the front that brought extreme heat to our area.
The complex of thunderstorms, known as a mesoscale convective system, or MCS, that moved through Iowa and Illinois began to move into the Ohio River Valley around noon time on June 29th. The weather recipe was in place for some fireworks to occur. Temperatures were incredibly hot, and summertime humidity was abounding, which resulted in a lot of potential energy in the atmosphere. The only thing needed for the recipe to be made was a match.The MCS that had moved through Illinois and Iowa provided that match. As temperatures soared into the 90s and 100s in the early afternoon, the MCS moved into this hot area. The complex created outflow, which is the wind that flows downward and outward from a storm system. This enabled the storm to continue creating more and more lift under its own thermodynamic processes, which would enable it to become a massive and powerful storm that would last several hours.
As the afternoon progressed, the Storm Prediction Center in Oklahoma became increasingly concerned for our area for our chances of severe weather. By 4 p.m. that afternoon, the Storm Prediction Center upgraded our area to a moderate risk for severe weather, which indicates a serious threat for severe weather.
As indicated by the description issued by the Storm Prediction Center, severe weather was already occurring well west and northwest of our area, with some areas in Indiana receiving wind gusts as high as 90 mph. Dayton, Ohio received a wind gust of 82 mph.
The storm was watched by many in our area Friday afternoon, as it continued to gain strength and propagate southeastward toward our area. Many wondered if, like many storms in the past, the thunderstorm complex would weaken as it moved into our area. However, temperatures were so hot outside (both Charleston and Huntington reached a staggering 103 degrees on June 29th) that it provided a plethora of energy for the storm to utilize as it moved toward our area, and it would ultimately not weaken.
For many, electric was knocked out before the storm even arrived. At its peak, over 600,000 customers (about 90%) in West Virginia were knocked out of power. Over 1 million customers in Virginia, 900,000 customers in Ohio and Maryland, and 150,000 customers in Indiana and New Jersey were also knocked out of power.
By July 5th, most electric customers in neighboring states had their electric back on. According to estimates from the National Weather Service, 226,000 customers were still without electric in West Virginia on July 5th (one week later), with Ohio coming in with the second-most outages at 139,000. Virginia, which at one point had over a million outages, had dropped their count to 89,000. Extreme heat accompanied the area the following days succeeding the derecho, causing dangerous health conditions for anyone trying to work outside.
As with most storms, the derecho began to show signs of weakening as it made its way over the spine of the Appalachian Mountains. This occurred mainly due to the lack of sunshine from the sun setting as it approached the mountains. The storm did not weaken immensely though, as wind speeds between 40 and 70 mph were still common over much of the Appalachian Mountains and into Virginia, causing extensive power outages. The derecho crossed the Appalachian Mountains around 8pm. The local airport at Elkins, West Virginia recorded a peak wind gust of 64 mph at 7:57 pm. Even Reagan National Airport near Washington DC recorded a peak wind gust of 71 mph later on that evening, which demonstrated the strength and endurance that this historic storm contained. By the time the storm reached the Atlantic Ocean and dissipated, the storm covered over 700 miles in distance, causing damage and power outages throughout its path.
The Storm Prediction Center received about 1,250 storm reports related to the derecho, about 1,175 of them being wind reports as you can see in the picture below denoting all of the storm reports received that day.